Prince William and Kate Middleton have significantly changed their approach at public engagements, in a reported attempt to prove that they are happy, and not "trapped" as claimed by Prince Harry.

In his tell-all interview with Oprah Winfrey in March, Harry said that he might not have stepped back from royal duties were it not for his wife Meghan, as he didn't know he was "trapped." He also said that he believes his father and elder brother, future heirs to the throne, are also "trapped within the system," like the rest of their family but "they don't get to leave."

According to royal biographer Duncan Larcombe, who wrote "Prince Harry: The Inside Story," William and Kate are "on the charm offensive" to refute Harry's claims about their thoughts on royal life. He told Closer magazine: "William and Kate have kept a dignified silence but now they're letting their actions do the talking."

"It's almost as if they're sending a secret message to Harry and Meghan saying, 'We're going to keep going, we're still here, we're not backing down, we're carrying on.' It's a message to Harry that life continues – with or without him," Larcombe explained.

In recent months, the Cambridges revamped their Instagram account, started a YouTube channel, and also shared clips of their behind-the-scenes goofy interactions. The couple also shared a personal video of themselves enjoying a day out with their three children, Prince George, seven, Princess Charlotte, six, and Prince Louis, three.

They also brought George along when they attended the European Championship final at Wembley, where their gestures presenting a warm family dynamic impressed royal fans. The Duke and the Duchess also attended a Wimbledon game together earlier this month, where they were spotted giggling and sharing jokes.

Duncan said about their recent engagements, "William and Kate are definitely on the charm offensive right now – and it's working." He claimed that there is "no doubt" they have taken Harry's allegations about William "trapped" in his role very seriously and are "determined to show that isn't the case," while noting that the Duchess in particular has appeared "all smiles" on recent engagements to show Harry and Meghan she is "happy and fun."

Royal expert Katie Nicholl also expressed similar sentiments, noting that the Cambridges have "solidified themselves as the nation's sweethearts more than ever recently in a quiet, dignified way."

"They've upped their game," she added.

The British royals
The British royals Photo: AFP / Paul ELLIS